# Help - length (object)

**URL:** <https://discourse.nodered.org/t/help-length-object/33317>\
**Category:** General\
**Created:** [24 September 2020 23:37 UTC](https://discourse.nodered.org/t/help-length-object/33317 "2020-09-24T23:37:25Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Ricardo-Miguel-Calde](https://avatars.discourse-cdn.com/v4/letter/r/9d8465/32.png) [@Ricardo-Miguel-Calde](https://discourse.nodered.org/u/Ricardo-Miguel-Calde)\
**Post date:** [24 September 2020 23:37 UTC](https://discourse.nodered.org/t/help-length-object/33317/1 "2020-09-24T23:37:25Z")

</div>

I want to enum/count each item (object) in DEVICES but lenght does not work... Can I be missing something please?

![Capture](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/4/d46c7ab22b76c9e364f8aa56e80477f926cf4fe9.png)

```auto
context.global.getDomainDevices = function(domain){
    //Gets all devices from a specific domain
    node.warn("getDomainDevices: Starting->" + domain);
    devices = global.get("DEVICES");
    ret="";
    for (i=0; i<devices.length; i++){
        node.warn("getDomainDevices: Item->" + devices[i]);
        if (devices[i].domain === domain){
            node.warn("getDomainDevices: Found->" + devices[i]);
            //It is part of this domain
            if (ret !== "" ){
                ret += "," + devices[i];
            }else{
                ret = devices[i];
            }
        }
    }
    node.warn("getDomainDevices: Result->" + ret);
    return ret;
}

```

---

<div class="post-metadata">

**Author:** ![knolleary](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/knolleary/32/3_2.png) [@knolleary](https://discourse.nodered.org/u/knolleary)\
**Post date:** [24 September 2020 23:45 UTC](https://discourse.nodered.org/t/help-length-object/33317/2 "2020-09-24T23:45:39Z")

</div>

Objects don't have a length property - only Arrays do (and Strings, but that's not relevant here).

To loop over its contents, you can do:

```auto
for (const key in devices) {
   const device = devices[key];
  //...
}

```

---

<div class="post-metadata">

**Author:** ![Ricardo-Miguel-Calde](https://avatars.discourse-cdn.com/v4/letter/r/9d8465/32.png) [@Ricardo-Miguel-Calde](https://discourse.nodered.org/u/Ricardo-Miguel-Calde)\
**Post date:** [24 September 2020 23:46 UTC](https://discourse.nodered.org/t/help-length-object/33317/3 "2020-09-24T23:46:24Z")

</div>

Thank you!

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [8 October 2020 23:46 UTC](https://discourse.nodered.org/t/help-length-object/33317/4 "2020-10-08T23:46:28Z")

</div>

Closed on 8 October 2020 23:46 UTC

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